When Nora Ephron succumbed to acute myeloid leukemia last June and died at age 71, the entertainment and media world was stunned. Part of the shock was that her illness had been kept out of the public sphere and her battles with the disease that claimed her life had been waged in private.

That was uncharacteristic for Ephron, the writer and director of "Sleepless in Seattle" and "You've Got Mail." The romantic comedy maven became a household name in part by drawing on her troubled marriage to philandering Watergate journalist Carl Bernstein in her best-selling roman à clef "Heartburn." As Ephron herself frequently said, (quoting her mother, screenwriter Phoebe Ephron) “everything is copy."

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So why had she decided not to turn her health issues into a memoir or column, as her friend Christopher Hitchens did with his own cancer fight?

The answer comes in a long and heartfelt personal essay about Ephron's final days in this week's New York Times Magazine, courtesy of her son, writer Jacob Bernstein.

Ephron was worried that "coming clean" with friends and colleagues would have a deleterious impact on her career.

"Certainly, she could continue writing books and essays," Bernstein writes. "But getting a movie made would be impossible, because no insurance company would sign off on it. Arguably, she could do a play, but bringing it to Broadway would be difficult, given that the development process takes years."

There was another reason, as well. Ephron's wit and myriad interests in everything from food to politics made her one of the most coveted tablemates in Hollywood. Yet, she was worried that going public with her disease would be a conversation killer.

"…what my mother didn’t want was to have her illness define her, turning every conversation into a series of 'how are you?'s," Bernstein writes.

As Bernstein implies, Ephron's personal ordeal may have influenced one of her final projects. "Lucky Guy," a new Broadway play starring Tom Hanks, opens next month. It centers on New York City columnist Mike McAlary, who got a Pulitzer Prize-winning scoop about police brutality after receiving a colon cancer diagnosis.